On May 31, 2018, we'll be retiring support for TLS versions 1.0 and 1.1 on all MailChimp sites, including MailChimp's API. This change improves the security of the data sent between you and MailChimp, whether you're accessing MailChimp through a browser, communicating directly with our API, or using one of our integrations. The technologies that ...

A few weeks ago, someone came into support because they couldn't get past the campaign builder’s recipients step. No amount of poking, prodding, clicking, or URL-mangling would permit them beyond choosing their recipients. Which is to say: they couldn’t click Send. Which is to say: MailChimp was broken. As it turns out, the bug was ...

Last month, we discussed our history with SSD-based servers and prepared a few tests to determine whether the performance rewards of SSDs would outweigh the risks involved for us going forward. Today, we'll take a closer look at OS tuning, filesystem mounting, and reveal the results of our testing. OS tuning In order to gain ...

At the end of this year, we’ll be retiring the older versions of MailChimp’s API. We announced the sunset earlier this year, but I wanted to provide some updates on improvements we’ve made to API v3.0 and some clarification on our plans. Our API team has been hard at work making it easier to manage ...

At MailChimp, we've historically had mixed feelings about SSD-based servers. Years ago, our servers were hosted by a provider that utilized SSDs for storage, and many of those SSDs ended up failing at the same time. It caused quite a few headaches for the team, and we were hesitant to consider SSDs as an option ...

Here at MailChimp, our operations team is in charge of the 1300+ physical servers that keep our app running strong. We couldn’t possibly provision, configure, and maintain all of those servers by hand, so we use a configuration management tool called Puppet to help us out. Puppet allows us to describe how the software across ...